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Humedales urbanos como infraestructura de re-mediación en el paisaje estuarino de Valdivia: red de drenaje urbano sostenible y Parque Fitodepurador Humedal Miraflores
No full textTesis (Magíster en Arquitectura del Paisaje)--Pontificia Universidad Católica de Chile, 2024Los humedales son áreas en las que el agua es el principal factor que determina el hábitat ofreciendo numerosos servicios ecosistémicos como la regulación climática, el control de inundaciones y la purificación del agua, sin embargo, son ecosistemas frágiles y amenazados. En la ciudad de Valdivia los humedales han formado parte del territorio mucho antes de su fundación y para el terremoto de 1960 el terreno se hundió, dando paso a inundaciones en las periferias de la ciudad que hoy en día se reconocen como humedales, los cuales han sido amenazados por el crecimiento urbano y sus transformaciones en el territorio. En Valdivia, los humedales urbanos forman parte del sistema de drenaje de aguas lluvia, debido a su rol natural de absorber y liberar el exceso de agua gradualmente, teniendo una capacidad de filtrar contaminantes. Sin embargo, el aumento de las inundaciones a causa de la impermeabilización de los suelos ha provocado un aumento del escurrimiento de las aguas, que traen toda la contaminación de la infraestructura urbana llegando directamente hacia estos ecosistemas y contaminando todo el sistema de aguas de la cuenca. De esta manera a causa de un sistema de drenaje en conflicto se producen inundaciones y contaminación en los humedales urbanos. Así la investigación se aborda a partir de tres escalas: territorial, urbana y proyectual, con el propósito de proponer soluciones frente a la degradación de los humedales en Valdivia.En la escala territorial se estudia el sistema hídrico de la cuenca del Rio Valdivia, como un sistema de aguas natural que se relaciona con un sistema artificial, integrando la topografía y crecimiento urbano de la ciudad, dejando en evidencia la ocupación de terrenos bajos que son particularmente vulnerables a las inundaciones. Revelando asi las principales causas de las inundaciones en la ciudad y sus características. En la escala urbana se caracteriza el sistema de drenaje urbano evidenciando su tensión con los humedales, centrándose en el Humedal Urbano declarado Miraflores- El Bosque-Las Mulatas-Guacamayo. Aquí la contaminación generada por la infraestructura urbana durante los episodios de escorrentía degrada el ecosistema, siendo el cabezal del sistema de humedales, situado dentro de la ciudad, el punto de mayor conflicto. La escala proyectual se establece a partir de las escalas previas de análisis contextual con enfoque propositivo, la cual se enfoca en remediar las aguas de escorrentía urbana mediante infraestructura verde azul, con el objetivo de mitigar las inundaciones y contaminación de los humedales. La propuesta se desarrolla en tres fases: un plan estratégico para conducir, infiltrar, almacenar y depurar las aguas lluvia; el desarrollo de una red de calles, plazas y parques; y la implementación del Parque Fitodepurador humedal Miraflores, diseñado para recibir la mayor carga de aguas contaminadas
On the Performance of an Air-Water Visible Light Communication System
No full textResearch on wireless communication in water environments is gaining attention due to its relevance in enabling and supporting new applications under the Underwater Internet of Things (UIoT) umbrella. Visible Light Communication (VLC) is one of the emerging communication technologies with the potential to contribute to this domain, especially concerning direct communications from above the surface to underwater nodes. Although more traditional radio frequency (RF) communications are not suitable for air-to-water communications, VLC offers unique opportunities in this area. In this respect, this work presents a simulative study attempting to theoretically understand the performance of VLC systems in both underwater and air-to-water channels. We explore performance metrics including, link gain, time delay, and bit-error rate, while analyzing the optical signal interruption on the sea surface due to water level changes. The investigation offers preliminary results that shed light on the feasibility and challenges of effectively enabling cross-border air-water communication systems using VLC technologies.Portuguese Foundation for Science and TechnologyMCTESUniversidad Diego PortalesEscuela de Informática y TelecomunicacionesSENESCYTCISTERFONDECY
Operando Optical Microscopy for Visualization of Dendrite Growth in an Argyrodite LPSCl-Polymer Composite Electrolyte
No full textHerein, we demonstrate the utility of optical microscopy as an accessible technique for the in situ visualization of dendrite growth within polymer-sulfide composite solid-state electrolytes. The composite electrolyte features in situ polymerization and cross-linking of the polymer between ceramic particles, which opens up extensive opportunities for accelerated materials discovery, given the vast array of acrylate/methacrylate monomers available. Specifically, the cross-linked polymer poly(triethylene glycol dimethacrylate) (poly(TEGDMA)) was observed to effectively fill pores and inhibit dendrite growth at the lithium metal interface, attributed to its glassy state at room temperature. This work represents the first application of optical microscopy to illustrate that the incorporation of glassy, undoped polymers such as poly(TEGDMA) can serve as a viable strategy for dendrite suppression in solid-state composite electrolytes.U.S. Department of EnergyLawrence Berkeley National LaboratoryLDRDOffice of ScienceOffice of Basic Energy Science
Seismic resilience of simply supported bridges subjected to subduction earthquakes
No full textSeismic resilience is essential for maintaining the functionality and safety of transportation infrastructure, especially in areas prone to subduction earthquakes. Simply supported bridges, which constitute a significant portion of highway networks, are particularly susceptible to damage caused by seismic events, often resulting in connectivity disruptions and expensive repairs. This study assesses the impact of various failure mechanisms on the seismic resilience of these structures, considering insights from the 2010 Maule earthquake in Chile. Fourteen bridge models were analyzed and designed according to the pre- and post-2010 Chilean seismic design code. Nonlinear dynamic simulations were performed using OpenSees, incorporating soil-structure interaction effects to capture realistic response behaviors. Fragility curves were developed for multiple damage states, and a resilience assessment framework was applied to quantify functionality loss and recovery time. Results evince that bridges designed under the updated seismic code exhibit lower probabilities of severe damage and faster recovery times, primarily due to improved detailing and increased structural capacity. These findings emphasize the necessity of incorporating performance-based seismic design principles that account for the interplay between failure mechanisms, repairability, and long-term functionality.ANID/FONDECYT No. 1231824; ANID/FONDECYT No. 1250712; Research Center for Integrated Disaster Risk Management (CIGIDEN); ANID/FONDAP 2023/1523A0009; ANID Doctorate Scholarships No. 21211554, No. 2121006
Altered Sensory and Stress Responses in Atopic Dermatitis: Effects of Acute Stress on Lesional and Non-Lesional Skin
No full textItch and pain are both mediated by small sensory fibres. Atopic dermatitis (AD) patients usually report stress-induced flares, but the impact of stress on sensory fibres in lesional and non-lesional skin remains inconclusive. This observational study assessed the effect of acute stress on sensory profiles in subjects with AD (n = 18) and healthy controls (HC, n = 21). Participants completed clinical and psychological questionnaires, and quantitative sensory testing was performed on lesional and non-lesional skin in AD and healthy skin in HC. Assessments were done before and after the Montreal Imaging Stress Task, an acute stress protocol. Stress responses were evaluated by anxiety ratings, heart rate (HR) and salivary cortisol (CORT). Cortisol binding globulin (CBG) was quantified as an indirect measure for circulating CORT. AD participants reported higher anxiety, depression and stress perception than HC. HR was similar between groups, but AD participants showed a blunted CORT response post-stress and lower CBG levels, suggesting altered stress regulation. Acute stress reduced cold sensitivity in HC and non-lesional AD skin but had no effect on lesions. These findings indicate that the effects of stress on small fibres depend on the condition of the skin and emphasise the sensory alterations experienced by AD patients.Agencia Nacional de Investigacion y Desarroll
Using a Bilingual R2L Adaptation to Develop Speaking Skills For Movie Reviews in an EFL Context
No full textTesis (Magíster en Lingüística Aplicada al Inglés como Lengua Extranjera)--Pontificia Universidad Católica de Chile, 2024.TESIS EMBARGADA POR EL ALUMNO HASTA EL 30 DE JUNIO DE 2026Action research project which examines the teaching of oral movie reviews in an eleventh-year class at a government-subsidised private school in Puente Alto, Chile. The primary research objective is to evaluate the impact of using a bilingual Reading to Learn (R2L) pedagogy to develop students’ speaking skills for the production of the movie review genre. Grounded in Systemic Functional Linguistics, this pedagogy informs the selection and analyses of model texts, as well as the language focus for teaching the review genre.The proposed R2L incorporates three iterative cycles of classroom activities designed to scaffold students’ progression from reading to orally producing the review genre through teacher guidance. Additionally, translanguaging strategies are integrated in the R2L to facilitate students’ understanding of the review genre and its language features, enabling them to produce oral texts on their own. These two theoretical frameworks – R2L and translanguaging – build the bilingual R2L pedagogy to support and enhance the students’ oral production in English of movie reviews.The findings from this pedagogical intervention reveal three key outcomes. First, the implementation of the proposed bilingual R2L significantly helped students to develop well-structured oral reviews. Second, the pedagogical strategies of the proposed bilingual R2L successfully provided students with appropriate language features to produce movie reviews orally. Third, the intervention improved students’ skills to employ evaluative language to engage and persuade their audience when reviewing movies in speech. For all these reasons, this action research demonstrates that a bilingual R2L adaptation positively impacts on students’ language development and their ability to produce oral movie reviews. By providing structured scaffolding and plenty opportunities for guided practice, this approach proves to be an effective method to improve students’ confidence and competence in the oral production of the review genre.The study reported in this thesis is an action research project which examines the teaching of oral movie reviews in an eleventh-year class at a government-subsidised private school in Puente Alto, Chile. The primary research objective is to evaluate the impact of using a bilingual Reading to Learn (R2L) pedagogy to develop students’ speaking skills for the production of the movie review genre. Grounded in Systemic Functional Linguistics, this pedagogy informs the selection and analyses of model texts, as well as the language focus for teaching the review genre. The proposed R2L incorporates three iterative cycles of classroom activities designed to scaffold students’ progression from reading to orally producing the review genre through teacher guidance. Additionally, translanguaging strategies are integrated in the R2L to facilitate students’ understanding of the review genre and its language features, enabling them to produce oral texts on their own. These two theoretical frameworks – R2L and translanguaging – build the bilingual R2L pedagogy to support and enhance the students’ oral production in English of movie reviews. The findings from this pedagogical intervention reveal three key outcomes. First, the implementation of the proposed bilingual R2L significantly helped students to develop wellstructured oral reviews. Second, the pedagogical strategies of the proposed bilingual R2L successfully provided students with appropriate language features to produce movie reviews orally. Third, the intervention improved students’ skills to employ evaluative language to engage and persuade their audience when reviewing movies in speech. For all these reasons, this action research demonstrates that a bilingual R2L adaptation positively impacts on students’ language development and their ability to produce oral movie reviews. By providing structured scaffolding and plenty opportunities for guided practice, this approach proves to be an effective method to improve students’ confidence and competence in the oral production of the review genre.2026-06-3
LSTM-Enhanced Deep Reinforcement Learning for Robust Trajectory Tracking Control of Skid-Steer Mobile Robots Under Terra-Mechanical Constraints
No full textAutonomous navigation in mining environments is challenged by complex wheel–terrain interaction, traction losses caused by slip dynamics, and sensor limitations. This paper investigates the effectiveness of Deep Reinforcement Learning (DRL) techniques for the trajectory tracking control of skid-steer mobile robots operating under terra-mechanical constraints. Four state-of-the-art DRL algorithms, i.e., Proximal Policy Optimization (PPO), Deep Deterministic Policy Gradient (DDPG), Twin Delayed DDPG (TD3), and Soft Actor–Critic (SAC), are selected to evaluate their ability to generate stable and adaptive control policies under varying environmental conditions. To address the inherent partial observability in real-world navigation, this study presents an original approach that integrates Long Short-Term Memory (LSTM) networks into DRL-based controllers. This allows control agents to retain and leverage temporal dependencies to infer unobservable system states. The developed agents were trained and tested in simulations and then assessed in field experiments under uneven terrain and dynamic model parameter changes that lead to traction losses in mining environments, targeting various trajectory tracking tasks, including lemniscate and squared-type reference trajectories. This contribution strengthens the robustness and adaptability of DRL agents by enabling better generalization of learned policies compared with their baseline counterparts, while also significantly improving trajectory tracking performance. In particular, LSTM-based controllers achieved reductions in tracking errors of 10%, 74%, 21%, and 37% for DDPG-LSTM, PPO-LSTM, TD3-LSTM, and SAC-LSTM, respectively, compared with their non-recurrent counterparts. Furthermore, DDPG-LSTM and TD3-LSTM reduced their control effort through the total variation in control input by 15% and 20% compared with their respective baseline controllers, respectively. Findings from this work provide valuable insights into the role of memory-augmented reinforcement learning for robust motion control in unstructured and high-uncertainty environments
Le cinéma de Guy Debord
No full textTraducción de Francisco Vega. El presente ensayo proviene de una conferencia ofrecida por G. Agamben en el contexto de un seminario consagrado a Guy Debord, acompañado de una retrospectiva de sus películas, en el marco de la Sexta Semana Internacional de Video de Saint-Gervains, Ginebra, en noviembre de 1995. La traducción se realizó con base en la versión publicada en Image et mémoire, France, Editions Hoëbeke, pp. 65-76; se tuvo también a la vista la versión en inglés traducida por Brian Holmes
Genotype-specific neoplastic risk profiles in patients with VHL disease
No full textHereditary tumor predisposition syndromes pose a challenge for early detection and timely treatment of tumors. In von Hippel-Lindau disease, desirable personalized surveillance programs are lacking due to insufficient data on genotype-specific risk profiles of individual mutations. To describe neoplastic risk profiles for carriers of pathogenic and likely pathogenic VHL germline mutations, our observational study recruited 1,350 participants from 40 centers worldwide. 432 different VHL germline mutations were observed, with p.Asn78Ser, p.Arg161Ter, p.Arg161Gln, p.Arg167Gln, p.Arg167Trp and p.Tyr98His being the six most frequent, occurring in a total of 493 carriers (36.5%) and in ≥30 patients each. Age-related penetrance risks for retinal hemangioblastoma, central nervous system hemangioblastoma, renal cell carcinoma, pancreatic neuroendocrine tumors and pheochromocytoma/paraganglioma in carriers of the most frequent VHL mutations were assessed. In addition, the number of organs affected, the frequency of surgery and the outcome are reported. Pairwise comparisons of the age-dependent tumor penetrance of these six mutations showed that 47 out of 90 pairs were significantly different. The most significant associations were found in p.Tyr98His (n = 19), followed by p.Arg161Ter (n = 10). All pairwise comparisons of mutations affecting different codons showed at least one significant (P < 0.05) difference, except for p.Asn78Ser vs p.Arg161Ter. Thus, tumor risk varied by VHL mutation type and location, but did not differ between the truncating mutation p.Arg161Ter and the missense mutation p.Asn78Ser. Our study demonstrates the importance of mutation-specific phenotype prediction. With appropriate validation, the data have important implications for risk assessment and decision making in tumor prevention for carriers of the respective VHL mutations.ANID/Fondecyt No. 1190419; ANID/ANILLO ACT21003